Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means that the car's computer thinks there isn't enough fuel in the engine when it's idling, like when you're stopped at a red light.
The engine control module (ECM) has detected that the air-fuel mixture is too lean on bank 1 (the side of the engine with cylinder 1) during idle conditions.
A P2187 code indicates that the ECM is detecting a lean condition (too much air and not enough fuel) in the engine's bank 1 while the vehicle is idling. This can be caused by a variety of issues, including vacuum leaks, faulty sensors, or fuel delivery problems.
• Rough idle
• Check engine light on
• Poor fuel economy
• Vacuum leak
• Faulty fuel injector
• Dirty mass air flow sensor
ECM: Engine Control Module
MAF: Mass Air Flow
• Check for vacuum leaks around the intake manifold.
• Inspect and clean the mass air flow sensor.
• Test the fuel injectors for proper operation.
• Replace any damaged vacuum hoses.
• Clean or replace the mass air flow sensor.
• Repair or replace faulty fuel injectors.
• OBD-II scanner
• Vacuum gauge
• Fuel pressure tester
$100 - $500
Moderate
• Ford Focus
• BMW 3 Series
• Volkswagen Jetta
• Regular maintenance of the air intake system.
• Ensure fuel injectors are clean.
• Regularly check for vacuum leaks.
Engine Performance
• Avoid driving the vehicle until the issue is diagnosed.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
P2187 is a common code for vehicles with vacuum leaks or issues with the air intake system.
Moderate – Addressing this issue promptly can prevent further engine damage.
Driving with a lean condition can cause engine damage and may not pass emissions tests.
• Engine at operating temperature
• Vehicle idling
Bank 1 refers to the side of the engine with cylinder 1, typically the driver's side in a V-type engine.
Q: Can I drive my car with a P2187 code?
A: It's not recommended to drive for long periods with this code as it can lead to engine damage.
Q: What causes a lean condition at idle?
A: Common causes include vacuum leaks, faulty sensors, or issues with the fuel system.
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Fitment Required · Vehicle-fitment part
Relevant for airflow, fuel-trim, and intake-metering faults after confirming the sensor is actually at fault.
Airflow and fuel-trim codes can involve the mass air flow sensor after proper diagnosis.
Verify the sensor design and fitment for your exact vehicle.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.